<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title></title>
    <style>
        .one{
            float: left;
            margin-right:-20px;
            margin-right: -100%;
            /*假设margin为-20px，那么后面的元素会重叠20px，假如此处为100%，那么就是自身完全重叠*/
            width: 100px;
            height: 100px;
            /*background-color: blue;*/
        }
        .two{
            float: left;
            width: 100px;
            height: 100px;
            /*background-color: red;*/
        }
    </style>
</head>
<body>
<div class="one">
    neoneoneoneo<br/>
    neoneoneoneo<br/>
    neoneoneoneo<br/>
    neoneoneoneo<br/>
    neoneoneoneo<br/>
    neoneoneoneo<br/>
</div>
<div class="two">
    tttttoneonet<br/>
    tttttoneonet<br/>
    tttttoneonet<br/>
    tttttoneonet<br/>
    tttttoneonet<br/>
</div>
</body>
</html>